Needle Valve Issue

[Sea Rider]

Need to fix the internal valve seat, an idiotic pseudo mechanic lightly scratched it trying to clean it out while poking it with something metal, needle which is brand new doesn't rest 100% properly on seat and there's a sligh carb fuel loss. It's mission impossible ordering a new one, would take too much moons to count with one. Be creative, chime your weirdest ideas to get done with this tech issue. Btw, it's a removable valve seat.

Happy Boating

 

[pvanv]

What motor, Luis?

 

[Sea Rider]

What motor, Luis?

Paul,

It's a 2 stroke Tohatsu 3.5 HP. Btw, what could be the cause of engine dying at idle, to restart need to move throttle lever slight passing starting mark and pull choke, if no choke it's impossible restarting the engine, no matter if already is sufficiently warm. Carb was in immaculate cond, was not gummed or rusted prior dismantling If adjusting idle rpm +,- with carb screw, rpm does not increase nor decrease a bit ? Engine works fine when passing idle to wot

Happy Boating

 

[pvanv]

If compression is OK, your carb is too lean. So the slight scratch in the seat may not be a problem. Is the mixture setting clip set too lean? Is the carb base o-ring sealing correctly? If the prior mechanic was poking with a wire, it may have had gunk that you now don't see. Did you soak it in a carb dip for a few hours?

 

[Sea Rider]

Paul,

Compression isn't top. The needle seat issue is just a small bowl fuel overflow. This portable has seen very low hours use as it's a J-24 emergency kicker. Carb has been fully cleaned just in case. Intake maifold has a new o'ring, which seals tight onto carb's throat along well adjusted band collar onto manifold. The mixture clip is set same as factory delivered. Pseudo mechanic luckily has not played with it.

Don't have carb soaking products down here, usually use car paint acrylic thinner when need to soak carb parts along generic carb spray overdoses. This small portable doesn't have an engine history as it's the first time has come completely dead to me after 3 years from original sale. Was about to be used as a second J-24 anchor...

Would a low compression engine experience overheat issues when going at 3/4 throtttle for say 15 minutes while pushing a boat ? Impeller and WP is in opt working state along peeing nicely and evenly ? Fuel/oil ratio was 45:1 when sea tested.

Happy Boating

 

[pvanv]

That motor can tolerate up to 100:1, so 50:1 factory recommendation is fine; no need to go to 45:1.
If the motor needs choke to start when warm, either there is a loss of vacuum (such as poor compression or a bad crank seal), or the carb is too lean. If the cooling system is pumping properly, an overheat is being caused by too much friction (heat being generated) or insufficient fuel (more fuel cools the motor somewhat -- too lean will be too hot). You may have a scored cylinder, etc. If running too lean, it will run hotter. One possibility is that the carb is too lean, causing too much heat, as well as stalling at low throttle.
I would try a different carb first as a test. You could try setting the mixture clip one step richer as well.

 

[Sea Rider]

Paul,

This portable has hidden issues, moron, pseudo mechanic stripped the whole crankcase down as the engine was not starting mainly because fuel **** small filter was obstructed, plug gapped too tight just 0.5 mm along a faulty ground ignition coil issue. Used cylinder head gasket, manifold gasket, lower base gasket & crankcase matting surfaces has been stupidly resealed with mega gray silicone.

Have not tested the engine at load while pushing a boat after the WP has gone through a exhaustive maintenance service, actual exiting water through peeing port is so hot that you could prepare a nice tea with it, imagine the front handle being more than warm when held.

Seems the mega gray silicone overdose has clogged some internal water passages and now engine cools much less than it should. Positively sure it's a overall gaskets/crankcase mating surface issue. Tuesday will test the engine again, if still overheats will dismantle power head down, check for scored cylinder wall, piston, piston rings cond. If shot will order a 0.5 mm piston/ring kit. Will post results.

Happy Boating

 

[Sea Rider]

Update:

Being owner not completely happy when first starting engine due to too much rope pulls, although engine was brought back to life when about to be used as a second anchor for a J-24. Ended stripping the whole powerhead down, as assumed earlier, some mega grey silicone was found slight clogging an internal water passage. This pseudo mechanic is soooo stupid that replaced the head gasket with one locally made, he forgot to tell gasket manufacturer to add a metal o'ring at center gasket.





Engine was losing compression through head gasket and poorly sealed powerhead mating surfaces. When making the ring test to check cylinder shape, cylinder was found bit oval at right side arrows, you can see bit light through when placed against a hard light. About 98% of all interior parts will be replaced for new along a 0.5mm piston/ring set. Rebuilding and making a exhaustive maintenence flywheel to prop, including parts, hand labor and machine shop costs will be around $500. With that amount owner will have a entire overhauled engine and working spot on as when out of the box for a second time.

Happy Boating